Reinforcement bar support

ABSTRACT

The proposed support is preferably constructed from high-compression concrete and may be custom-dimensioned according to project requirements. The support may have one or more bearing pads at one or more heights which may include one or more anchoring arms. The support may include a bore sized to accommodate a range of rebar sizes. A length of pre-cut angled rebar may be may be cast in place or may be secured within the bore by epoxy or other means at the time of manufacture or in the field. To maximize stability and overcome low soil-bearing capacity, the bottom surface area of the support is preferably larger than the bearing pad surface area. At least two opposing sides of the support include at a shear-key to anchor the support within the finished slab.

FIELD OF THE INVENTION

The present invention relates to improved technology in the field ofreinforcement bar support structures used in concrete construction, andmore particularly to an economical, precast, high-compression concretesupport structure which has a size and overall configuration that isapplication-specific, which has a footprint that overcomes lowsoil-bearing capacity where the support is used directly adjacent grade,which eliminates the need for continuous runners on metal decking, whichstably supports reinforcement material prior to placement of wetconcrete during slab formation, which facilitates convenient tie wireattachment of reinforcement material with a minimum of effort, and whichinterlocks with the finished concrete slab.

BACKGROUND OF THE INVENTION

Various structures are currently available for supporting reinforcementbar (rebar) prior to pouring concrete to form a slab. The support isneeded to raise the rebar to a sufficient height to embed it properlywithin the resulting slab. One widely used conventional supportstructure is a “wire chair,” which typically consists of two or moremetal legs, usually steel. Wire chairs may include only a few legs ormay include multiple sets of legs with one or more bolsters extendingbetween them. Bolstered wire chairs are generally more expensive thansmaller chairs, but their narrow footprint makes them one of the onlyoptions currently available for use on corrugated metal decking such asthat which typically underlays second or greater story slabs.

Because most wire chair legs are small diameter, they are prone to sinkinto subgrade when used directly adjacent grade, especially whereexpansive soil conditions exist, for example in low-lying areas.Although some wire chairs include feet or dowels which extend parallelto ground, the feet are usually so small that this added protectionagainst sinkage is negligible. Sinking can cause the wire chairs toprotrude from the resulting slab and wick moisture into the slab and tothe rebar, which may lead to rust and/or structural weaknesses. As aresult, most wire chairs require plates affixed to the legs to enlargethe footprint area. The cost of wire chairs increases based on size andquantity of additional foot plates necessary to avert sinkage. Evenwhere the cost of plate-enhanced wire chairs may be feasible, theincreased footprint area they may provide may still be insufficient toappreciably prevent sinkage. The spindly structure of wire chairs alsomakes them especially prone to inadvertent lateral displacement.

Another concern with wire chairs is their propensity to form rust. Thismay be especially problematic in finished overhead slabs where any rustthat forms may be visible and may also come into contact with humidityor rainwater and cause damaging runoff (for example, to vehicles parkedin cement parking garage structures). Consequently, wire chairs for usein overhead slabs generally require the added expense of plastic tips,epoxy, or some other protective coating to try to prevent rust withvarying degrees of success.

Finally, the price of even the most simple conventionally available wirechairs can be quite high, which can significantly impact total cost ofconstruction where large numbers of wire chairs are needed. Incommercial building projects, it is not unusual to need as many as30,000 wire chairs. Cost is greater where coated chairs are necessary.The cost may increase even further where bolstered chairs are needed formetal decking. Finally, in thicker concrete slabs with more than onelayer of reinforcement, the number of chairs needed may easily double.

The high cost of wire chairs may lead builders to use shorter, lessexpensive chairs that fall shy of the 3-inch minimum height required bynational building code. Cutting chair height could compromise thestructural integrity of the finished slab since the height of the chairsdirectly affects placement of reinforcement within the slab.

Other conventional rebar supports include dobies, often available onlyin pallet quantities. In plainest form, a dobie is a 6-sided square orrectangular block around which tie wire must be wrapped to when securingsupported rebar. Wire wrapping the circumference of the dobie requiresdisplacing the dobie, which may be problematic where initial placementis important. Further, circumferential wrapping requires significanttime and labor, more so in sizeable construction projects. Plain dobiesalso include no features for keeping rebar in position, which mayincrease time and labor required if repositioning is necessary prior towiring the rebar in place. Limited availability may also negativelyimpact costs where odd or ongoing quantities are needed. Finally,because the plain dobie is smooth-sided, it does not integrate with thefinished slab. Consequently, a sizeable cold joint is created, which maycause the dobie to shift or settle and could lead to structuralweaknesses in the finished slab.

A second type of conventionally available dobie is essentially identicalto the plain dobie except that it includes a set of tie wires with whichto secure supported rebar. The tie wires are typically 16-gauge annealedwire, which easily forms rust with exposure to the elements andsubsequently becomes brittle and prone to breakage. This is especially aconcern where the dobie will not be used immediately and may be exposedto moisture in the interim between acquisition and usage, almost alwaysthe case in construction projects. Despite the high potential forbreakage of tie wires, the wire dobie may be up to 70% more costly thanthe plain dobie. Further, where breakage occurs, time and labor islikely to be lost on circumferential wrapping just as with the plaindobie.

A third type of conventionally available dobie is a combination dobie.The combination dobie has an elongate rectangular shape that allows foruse at one of two heights depending on whether it is positioned on ashort side or a long side. Combination dobies include a channel forkeeping supported rebar in position prior to wiring, usually along onelong side and one short side. During use, at least three sides of thecombination dobie will remain unintegrated with the finished slab,making it subject to the same cold joint problems described above.Moreover, time and labor is likely to be lost on circumferentialwrapping just as with the plain dobie.

A fourth conventionally available dobie is a dowel dobie, similar to thecombination dobie except that one of the two channels is replaced by ahole. The channel may be used to support a reinforcing mat at a lowerheight, or the hole may be fitted with rebar to elevate a reinforcingmat. Because a single channel (or alternatively the hole) will notsufficiently anchor the dowel dobie within the finished slab, settlingand slab integrity are still concerns.

Another conventional structure for supporting rebar, yet one which isnot generally approved by structural engineers or inspectors, isconcrete brick, usually constructed from lower-strength (typically 1500psi) concrete. National building standards require at least 3 inchesbetween a reinforcing layer and grade, necessitating a minimum 3-inchsupport. Despite the fact that concrete bricks may not satisfy code,contractors often resort to using them because they may be cheap and,positioned with their largest surface area side adjacent soil, they mayovercome low soil-bearing capacities better than currently availablealternatives.

What is therefore needed is a structural support which is constructed ofhigh-compression concrete, can stably support reinforcement materialsduring concrete slab formation, is designed to overcome low soil-bearingcapacities, eliminates the need for bolstered chairs on metal decking,minimizes the possibility of rust in the finished slab, facilitatesconvenient tie wire attachment with minimum effort, securely integrateswith the finished slab to minimize the possibility of settling andshifting, is pre-cast to satisfy code and construction specifications,yet is economical.

SUMMARY OF THE INVENTION

The support of present invention is affordable, effective, and superiorto conventionally available alternatives. The proposed support may bepre-cast to specification. The support is preferably constructed ofhigh-compression concrete, typically exceeding 2,500 psi. The overallshape of the support may be, but is not limited to, any shaped baseleading up to an upper surface and may be frusto-pyramidal with aslittle as three sides, to an infinite number of sides (of any shape) toapproach a frusto-conical shape, as well as any other shape which lendsitself to the present invention. The height of the support may varybased on the height of the slab, the relative height needed for therebar reinforcing layer, or code requirements. The support may be castwith multi-level bearing pads where a single slab will include more thanreinforcing layer. The width and length of the support may be variedaccording to structural engineering and code requirements of a givenconstruction project.

The support may include one or more anchoring arms which may be sizedaccording to the size of reinforcement material to be supported. Theanchoring arms are preferably constructed from steel, including, but notlimited to, plain, hot dipped galvanized, or stainless. Reinforcementmaterial may be conveniently wired to one or both anchoring arms withoutdisplacing the support. The anchoring arms may be cast in place duringmanufacturing, and may preferably be situated a sufficient distance fromthe edges of the bearing pad surface to prevent the finished slab fromcracking over the anchoring arms.

The support may include a blind bore which may be sized to accommodate arange of rebar sizes. Pre-cut angled rebar may be fixed in the bore atmanufacture or in the field for supporting a reinforcing mat orpost-tension cable at an elevated height. The rebar may be secured inthe bore by epoxy or other effective means or may even be cast in place.

The base of the support is preferably larger than the bearing padsurface area to maximize stability, to overcome low soil-bearingcapacity, and to broaden the variety of applications in which thesupport can be used effectively. The sides of the support are preferablysloped, with slope dependent upon both the height of the support and thedimensions of the bearing pad surface and base. Because the support ispreferably constructed entirely of concrete with no metal projectionswhich may form rust, the potential for exposed rust in a finished slabis virtually eliminated. The support may also be used successfully oncorrugated metal decking as the base may be easily sized to spanadjacent ridges or fit within the troughs between ridges.

The support may preferably include one or more shear-keys to help anchorthe support in the finished slab. The shear-keys may be any of a varietyof shapes, including, but not limited to, cylindrical, square,trapezoidal, pyramidal, angular, or other.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, its configuration, construction, and operation will bebest further described in the following detailed description, taken inconjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a first embodiment of the support of thepresent invention having a cylindrically-shaped shear key on each of twoopposing sides and a bearing pad with a pair of anchoring arms extendingtherefrom;

FIG. 2 is a side view of the support of FIG. 1 in which the full lengthof one of the cylindrically-shaped shear keys and one of the anchoringarms is visible, and FIG. 2 further details the anchoring arm;

FIG. 3 is a perspective view of a second embodiment of the support ofthe present invention having a cylindrically-shaped shear key on each oftwo opposing sides and having a blind bore opening onto a bearing pad;

FIG. 4 is a side view of the support of FIG. 3 in which one of thecylindrically-shaped shear keys is visible, and illustrates furtherdetails of the blind bore and includes a length of rebar verticallypositioned in the blind bore;

FIG. 5 is a perspective view of a third embodiment of the support of thepresent invention having a cylindrically-shaped shear key on each of twoopposing sides and a bearing pad with an anchoring arm extendingtherefrom and a blind bore therein;

FIG. 6 is a side view of the support of FIG. 5 in which one of thecylindrically-shaped shear keys is visible, and illustrates furtherdetails of the anchoring arm and the blind bore and includes a length ofrebar positioned vertically within the blind bore;

FIG. 7 is a perspective view of a fourth embodiment of the support ofthe present invention having a cylindrically-shaped shear key on each oftwo opposing sides, an angled shear key, a blind bore opening onto anupper bearing pad, and an anchoring arm extending from a lower bearingpad;

FIG. 8 is a side view of the support of FIG. 7 in which the angled shearkey and one of the cylindrically-shaped shear keys is visible, andillustrates further details of the anchoring arm and blind bore andincludes a length of rebar positioned vertically in the blind bore;

FIG. 9 is a plan view of the support of FIG. 5 which illustrates thepositioning of the support relative to two reinforcing layers within asingle concrete slab;

FIG. 10 is a plan view illustrating installation of the support of FIG.3, including a post-tension cable sheath and enclosed cable suspendedfrom a pair of supports;

FIG. 11 is a top view of a gang form with multiple compartments forconstructing multiple supports simultaneously;

FIG. 12 is a top view of a bearing plate insert which includes a throughbore and a support groove;

FIG. 13 is a cross-sectional view of the compartment of FIG. 11outfitted for constructing supports such as the third embodiment of thesupport;

FIG. 14 is a cross-sectional view of the compartment of FIG. 11outfitted for constructing supports such as the fourth embodiment of thesupport;

FIG. 15 is a top view of a fifth embodiment of the support of thepresent invention having a blind bore, an anchoring arm, three slopedsides, a shear key, and an overall frusto-pyramidal shape;

FIG. 16 is a top view of a sixth embodiment of the support of thepresent invention having a blind bore, an anchoring arm, eight slopedsides, a shear key, and an overall frusto-pyramidal shape;

FIG. 17 is a top view of a seventh embodiment of the support of thepresent invention having a blind bore, an anchoring arm, one continuoussloped side, a shear key, and an overall frusto-conical shape; and

FIG. 18 is a top view of an eighth embodiment of the support of thepresent invention having a blind bore, a pair of anchoring arms, onecontinuous sloped side, a pair of shear keys, and an overall elongatefrusto-conical shape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The description and operation of the invention will be best initiatedwith reference to FIG. 1, which is a perspective view of a firstembodiment of the bar support 51 of the present invention which is idealfor slabs under 8 inches thick requiring only a single layer ofreinforcement. Support 51 may preferably be constructed of ahigh-compression concrete such as 2,500 psi or greater. Support 51 maybe frusto-pyramidal shaped, the embodiment shown being a pyramid withfour sides, but which may also have three sides, or more than foursides, or any up to an infinite number of sides, and the shape of whichmay also be conic, cylindrical, or frusto-conical. The support 51 mayhave a first side 55, a second side 57, a third side 61 oppositelydisposed from first side 55, and a fourth side 63 oppositely disposedfrom second side 57.

Support 51 may have a bearing pad surface 65 and a base surfaceindicated by hooked arrow 67. The area of base 67 may preferably belarger than that of bearing pad surface 65 to increase stability ofsupport 51 and facilitate ease of use in a variety of applications. Thelarger area of base 67 is ideal where soil-bearing capacity is lessenedby wet conditions such as those in low-lying areas or where undergroundwater is a concern. Additionally, because base 67 may be customized to agiven size, support 51 is optimal for use on metal decking, wherecorrugations make the use of conventional supports difficult becausethey may tilt if the base size is only slightly larger than acorrugation trough.

Bearing pad surface 65 may include a first anchoring arm 69 and possiblya second anchoring arm 71. Anchoring arms 69 and 71 may preferably beconstructed from bent rods of any cross sectional shape which maypreferably range from 3/32 to ⅜ inch in diameter, depending on the sizeof rebar to be supported and engineering specifications. Anchoring arms69 and 71 may preferably be fabricated from steel, which may be, but isnot limited to, plain, hot dipped galvanized, mill galvanized, orstainless. Anchoring arms 69 and 71 may preferably be cast in place insupport 51 and positioned ¼ to ¾ inch from edges of bearing pad surface65 to prevent the finished slab from cracking over anchoring arms 69 and71.

First side 55 may include a first shear key 75 and third side 61 mayinclude a second shear key 77. A third or fourth shear key may also bepresent. The overall shape of support 51 and opposing shear keys 75 and77 help to anchor support 51 in place, potentially minimizing shiftingand settling and the consequent potential for developed structuraldeficiencies in the finished slab.

Although support 51 is illustrated in FIG. 1 as having two shear keys 75and 77, any or all of sides 55, 57, 61, and 63 may conceivably includeother shear keys. Shear keys 75 and 77 are illustrated in FIG. 1 ascylindrically-shaped voids but may be any shape forming an irregularity,including, but not limited to, square, rectangular, trapezoidal,angular, or other shape that would facilitate anchoring support 51 inplace in a finished slab. Because strength of shear keys 75 and 77 willbe determined by the strength of concrete in the finished slab, support51 may preferably be constructed from about the same or greater strengthconcrete as that of the finished slab.

Also illustrated in FIG. 1 are dimensions of support 51. Overall heightH1, measured from bearing pad surface 65 to base 67, may be from about ¾to about 12 inches, depending on the planned slab thickness, thethickness of concrete required above the level of reinforcement and/orbuilding code. Width W1 and length L1 of bearing pad surface 65 may eachrange from about 1 to about 4 inches and may be driven by H1 and thesize of base 67. Width W2 and length L2 of base 67 may each range fromabout 4 to about 12 inches. Area of base 67 may be prescribed based uponsoil conditions or other engineering concerns.

Based on the possible measurements for H1, W1, W2, L1 and L2, angle αmay range from about 97° (at maximum H1 of 12 inches, minimum W1 and L1of 1 inch, and minimum W2 and L2 of 4 inches) to about 170° (at minimumH1 of ¾ inch, maximum W1 and L1 of 4 inches, and maximum W2 and L2 of 12inches). Similarly, angle β may range from about 10° to about 83°.Because support 51 is symmetrical, the possible ranges of angles δ and εwill be similar to those described for angles α and β.

FIG. 2 is a side view of support 51 of FIG. 1 in which first side 55,first cylindrically-shaped shear key 75, and first anchoring arm 69 arevisible. The depth of shear key 75 measured from first side maypreferably be about ¼ inch to ensure a shear strength sufficient to keepsupport 51 in place in the finished slab, but may also be as great as ½inch, for example where height H1 exceeds 6 inches and the area of base67 exceeds 36 inches. Distance D1 between bottom edge of shear key 75and base 67 may preferably be about ¾ inch, but may exceed ¾ inch ifengineering specifications require.

Height H2 of anchoring arm 69 relative to bearing pad surface 65 maypreferably be about ⅜ to about 1 inch. Depth D2 of anchoring arm 69 insupport 51 may preferably be about ½ to about 2.5 inches. FIG. 3illustrates anchoring arm 69 as a nail having a nailhead 79 and, tip 81,and main body 83, but anchoring arm 69 could conceivably be reversed180°, and either end of anchoring arm 69 could include an end such asnailhead 79 having a circumference greater than the circumference of theexposed portion of anchoring arm 69, the term “circumference” notlimiting the shape of anchoring arm 69 but including the sum of thecross-sectional boundary lengths of any of a variety of possible crosssectional shapes. Further, anchoring arm 69 could conceivably be asimple rod which may have a cross-sectional diameter of any shape, suchas round, square, octagonal, triangular, or any other shape, and whichmay have straight ends or may include angled ends to help secureanchoring arm 69 withing support 51.

FIG. 3 is a perspective view of a second embodiment of the bar support85 of the present invention which is ideal for use in slabs under 6 feetthick requiring only a single reinforcing mat. Support 85 has dimensionssimilar to those described for support 51 in FIGS. 1 and 2. Rather thanhaving anchoring arms, support 85 may include a blind bore 87 extendingpartially through support 85 and opening onto bearing pad surface 65 atopening 89.

FIG. 4 is a side view of support 85 of FIG. 3 in which shear key 75 isvisible, and FIG. 4 further illustrates a length of angled rebar 91positioned vertically in bore 87. Rebar 91 may preferably include a bendof about 90 degrees, creating a horizontal portion 93 and a verticalportion 97. Horizontal portion 93 facilitates support of either a singlereinforcing mat or a post-tension cable at a specified elevation. Toensure that a reinforcing mat will be supported at the proper height,vertical portion 97 of rebar 91 may be cast in place or may be otherwisefixed in place in bore 87 during manufacture, preferably using a gluecement, such as epoxy. Alternatively, rebar 91 may be secured in placein the field using epoxy or any other means by which rebar 91 may befixed at the proper height.

D3 indicates the depth of bore 87 in support 85. To effectively supportrebar 91, bore 87 may preferably be at least 2 inches deep. Further, foroptimal structural integrity of support 85, there may be at least oneinch between bottom of bore 87 and base 67. Consequently, H1 for support85 may preferably be at least 3 inches to accommodate bore 87.

Diameter D4 of bore 87 and opening 89 may be sized to accommodate rebarfrom about ⅜ inch (#3 bar) to about 1 inch (#8 bar). Though FIG. 4illustrates horizontal portion 93 of rebar 91 in a random position,rebar 91 may be rotated 360° in any direction prior to being secured inbore 87. Rebar 91 may preferably be grade 60 (60,000 psi tensilestrength) or better, free of rust scale, and may be epoxy coated toprevent rust formation.

Height H3 may be determined by where the reinforcing mat is to belocated within the finished slab. If necessary, height H4 may also bevaried by vertically adjusting rebar 91 prior to securing it in bore 87.

FIG. 5 is a perspective view of a third embodiment of the bar support 99of the present invention which is ideal for use in slabs requiring bothan upper and a lower reinforcing mat. Support 99 may have a first shortside 103, a first long side 105, a second short side 109 oppositelydisposed from first short side 103, and a second long side 111oppositely disposed from first long side 105. Like supports 51 and 85described in FIGS. 1 through 4, first short side 103 of support 99 mayinclude a first shear key 113 and second short side 109 may include asecond shear key 117. Any of sides 103, 105, 109, and/or 111 mayconceivably include other shear keys of the same or other shape. Support99 may also include a bearing pad surface 119 and base 121.

Support 99 may include a blind rebar support bore 123 extendingpartially through support 99 and opening onto bearing pad surface 119 atopening 125. In addition to support bore 123, support 99 may include ananchoring arm 127 subject to specifications similar to those describedfor anchoring arms 69 and 71 of FIGS. 1 and 2 above.

FIG. 5 illustrates salient dimensions of support 99, which are similarto those described for support 51 of FIGS. 1 and 2 and support 85 ofFIGS. 3 and 4, with the exception of width W1 and width W2, which may begreater than those specified for supports 51 and 85 to insure sufficientspace for securing both support bore 123 and anchoring arm 127 and toprovide sufficient lateral stability once a second level ofreinforcement is introduced. Accordingly, W1 and L1 for support 99 mayboth range from about 1 to about 4 inches. W2 may range from about 6 toabout 12 inches, and L2 may range from about 4 to about 10 inches.

Angle α in FIG. 5 may range from about 94° (at maximum H1 of 12 inchesand minimum L1 of 1 inches, W1 and L2 of 4 inches, and W2 of 6 inches)to about 166° (at minimum H1 of ¾ inch and maximum W1 of 6 inches, L1 of4 inches, W2 of 12 inches, and L2 of 10 inches). Similarly, angle β mayrange from about 86° to about 14°, angle δ may range from about 97° toabout 144°, and angle ε may range from about 83° to about 36°.

FIG. 6 is a side view of support 99 of FIG. 5 in which shear key 113 isvisible, and FIG. 6 further illustrates a length of rebar 131 positionedvertically in support bore 123. Rebar 131 is subject to specificationssimilar to those described for rebar 91 in FIG. 4 and may be similarlyangled to form a horizontal portion 133 and a vertical portion 135.

Measurements H2, H3, H4, D2, D3 and D4 are all subject to specificationssimilar to those described for similar features in the previous figures.Anchoring arm 127 is subject to specifications similar to thosedescribed for anchoring arms 69 and 71 of FIGS. 1 and 2, including 137and tip 139.

FIG. 7 is a perspective view of a fourth embodiment of the bar support143 of the present invention which is ideal for use in slabs on elevateddecking where both an upper and a lower reinforcing mat are required.Support 143 is essentially a two-level version of support 99 whichcombines the longer base length of support 99 of FIGS. 5 and 6 with bothan upper bearing pad surface 147 and a lower bearing pad surface 149.Support 143 may be defined by a first side 151, a second side 153, anthird side 155 oppositely disposed from first side 151, a fourth side159 oppositely disposed from second side 153, and a fifth side 161adjacent lower bearing pad surface 149. Support 143 may also include abase surface 163.

First side 151 may include a cylindrically-shaped first shear key 165and third side 155 may include a cylindrically-shaped second shear key167 adjacent lower bearing pad surface 149. An angled third shear key171 may be defined by fifth side 161. Shear keys 165, 167, and 171 arenot constrained by the shapes shown, but may be any shape which helps toanchor support 143 in a finished slab.

Support 143 may include a blind bore 173 opening onto upper bearing padsurface 147 at opening 175 and an anchoring arm 177 on lower bearing padsurface 149. The specifications for bore 173 and anchoring arm 177 aresimilar to those described for similar features of support 99 in FIGS. 5and 6.

Width W1 of upper bearing pad surface 147 may range from about 1 toabout 10 inches, and length L1 may range from about 1 to about 8 inches.Width W2 of base 163 may range from about 6 to about 12 inches andlength L2 of base 163 may range from about 4 to about 10 inches. WidthW3 of lower bearing pad surface 149 may range from about 1 to about 10inches, and width L3 may range from about 1 to about 8 inches.

Angle α may range from about 101° (at maximum H1 of 12 inches, andminimum W1 and L1 of 1 inches, W2 of 6 inches, and L2 of 4 inches) toabout 144° (at minimum H1 of ¾ inch and maximum W1 of 10 inches, L1 of 8inches, W2 of 12 inches, and L2 of 10 inches). Angle β may range fromabout 79° to about 36°.

Although lower bearing pad surface 149 is shown with L3 equal to L2, L3may be narrower than L2, for example if lower bearing pad surface 149was tapered or if second and fourth sides 153 and 159 were indentedalong lower bearing pad surface 149. Conversely, L3 may be greater thanL2 if second and fourth sides 153 and 159 were widened along lowerbearing pad surface 149. Furthermore, although second and fourth sides153 and 159 are shown as having a continuous slope from first side 151to fifth side 161, their slope could conceivably change between upperbearing pad surface 147 and lower bearing pad surface 149. For example,second and fourth sides 153 and 159 may be angled farther inward towardlower bearing pad surface 149 or farther outward away from lower bearingpad surface 149.

FIG. 8 is a side view of the support 143 looking along line 8-8 of FIG.7. Ranges for D2, D3, D4, H1, H2, H3, and H4, are similar to thosedescribed for similar features of support 99 in FIGS. 5 and 6. Forelevated decking, code generally requires that a lower reinforcing matbe no less than ¾ inch from the decking. Accordingly, height H5 betweenlower bearing pad surface 149 and base 163 may range from about ¾ inchesto about 2.75 inches. Angle δ may range from about 97° at maximum H1 toabout 144° at minimum H1. Angle ε may range from about 83° to about 36°.

For structural soundness, the angular shape of third shear key 171 maypreferably be employed only where H5 is less than about 1.5 inches. Thefeatures of anchoring arm 177 are similar to the features of anchoringarms described in previous figures, including nailhead 179 and tip 181.

FIG. 9 is plan view which illustrates support 99 in a finished concreteslab 183 adjacent grade 185. First long side 105 of support 99 andprofiles of first and second shear keys 113 and 117 are visible. A firstreinforcing bar 187 may be secured to anchoring arm 127 with tie wire189 and may be a component of a lower reinforcing mat 191. A secondreinforcing bar 195 may be secured to horizontal portion 133 of rebar131 with a first tie wire 197 and may be a component of an upperreinforcing mat 199. Upper reinforcing mat 199 may be secured to secondreinforcing bar 195 by a second tie wire 201. Finished slab 183,including top surface 203, results from pouring concrete over support 99above grade 185.

FIG. 10 is 2-dimensional installation view illustrating two supports 85which are similar in appearance but which may or may not be identical.Supports 85 are shown elevating a post tension cable sheath 207 andenclosed wire 209. Each support 85 is shown adjacent grade 211 withfirst short side 103 and first shear key 75 visible. Post tension cablesheath 207 with enclosed wire 209 may be extended over horizontalportion 93 of rebar 91 of each support 85 and may be secured by tie wire213. Base 67 is designed to optimize stability and minimize slack inpost tension cable sheath 207 and enclosed wire 209 as most applicationsgenerally require post tension cable sheath 207 to be as straight aspossible prior to pouring the planned slab.

A description of the process used to form various embodiments of thesupport of the present invention is best initiated with reference tosupport 99, although the process may be used to form any of supports 51,85, 99, or 143 in the previous FIGS. 1 through 10 or any of supports287, 301, and 315 in subsequent FIGS. 15 through 17.

FIG. 11 is a top view of an empty gang form 215. Gang form 215 may beconstructed from any of a variety of materials, though wood is ideal forcost and availability. For simplicity, gang form 215 is illustrated withonly two compartments 217, each of which has a floor 219, a first shortside wall 221, a first long side wall 223, a second short side wall 227,and a second long side wall 229. In fact, gang form 215 may have anynumber of compartments 217. Additionally, although each compartment 217is shown as generally rectangular, each may also be generally square orany other shape which facilitates formation of the proposed support.

FIG. 12 is a perspective view of a bearing plate insert 231 for use ingang form 215 of FIG. 11. Bearing pad insert 231 may have a top surface233, bottom surface 234, first short side wall 235, a first long sidewall 239, second short side wall 241, and second long side wall 243, allof which may be complimentary in length and slope to side walls 221,223, 227, and 229 of compartment 217. Although bearing pad insert 231may include a through bore 245 and a support groove 247 bisecting topsurface 233, it is conceivable for bearing pad insert 231 to have anynumber of similar through bores and/or grooves, depending on the type ofsupport to be formed.

Continuing to use support 99 as an example, to achieve the proper heightbetween anchoring arm 127 and bearing pad surface 119, groove 247 maypreferably be from about ½ to about ¾ inch deep, the depth beingsufficient to support the “nail” without an interference fit. Groove 247may extend completely across bearing pad insert 231 to allow for customlength or placement of an anchoring arm. Groove 247 may preferably befrom about ¼ to about ⅛ inch in diameter. Similarly, through bore 245may preferably have a diameter from about ½ to about 1 inch toaccommodate various rebar sizes.

FIG. 13 is a cross-sectional view of a compartment 217 of gang form 215of FIG. 11 which has been outfitted to form a support such as support 99of FIGS. 5 and 6. Bearing pad insert 231 may preferably be adjacentfloor 219 such that side walls 235 and 241 are adjacent side walls 221and 227, respectively, of compartment 217. A sealant 249, such as caulkor tape, may be used to seal any gaps between bearing pad insert 231 andside walls 235, 239, 241 and 243 of compartment 217.

Bearing pad insert 231 is shown with anchoring arm 127 inverted insupport groove 247 and a dowel 251 inserted in through bore 245 to formrebar support bore 123. Dowel 251 may vary in height depending upon thedesired depth of a given bore. A liner 253 may be seen adjacent sidewalls 221 and 227 and may preferably extend along all side walls ofcompartment 217. Liner 253 may preferably be constructed from materialwhich will facilitate easy removal of a finished support fromcompartment 217, such as plastic, vinyl, or metal, for example. Further,liner 253 may be coated with a release agent prior to pouring support 99to make the resulting support 99 easier to remove from form 215.

A first shear key insert 255 may preferably be installed adjacent orattached to liner 253 along first short side wall 221 and a second shearkey insert 257 may preferably be installed adjacent or attached liner253 along second short side wall 227. Shear key inserts 255 and 257 areillustrated as cylindrically-shaped but may be any shape, includingtrapezoidal, square, angled, or pyramidal, for example. Other shear keyinserts may be added as necessary.

FIG. 13 illustrates a container 259 from which high-compression concrete263 may be poured into compartment 217. At an end-user's option,concrete test cylinders may be made and tested for strength to ensurecompliance with American Concrete Institute standards. Preferably,concrete 263 may be prepared no more than 30 minutes prior to pouringand may be poured in 1-inch layers. Each layer may preferably beconsolidated (for example by smoothing with a cylindrical rod) prior topouring successive layers. The final layer of concrete 263 maypreferably be leveled even with the top edge of form 215 and smoothedwith a leveling bar to produce a flat finish on the exposed base 121.

After approximately 4 to 6 hours, support 99 may be removed fromcompartment 217 by inverting form 215 and gently tapping to break anybonds between form 215 and concrete 263. Once support 99 is free of form215, form 215 may be lifted away, leaving liner 253 in place to protectsupport 99 from vibration and movement as it continues to cure.Optimally, support 99 should be cured at least 24 hours before removingit from liner 253. During the curing process, base 121 may be engravedwith information which may include, but is not limited to,specifications of the support useful for forensic purposes.

Rebar 131 may preferably be cut to a pre-specified length according toproject requirements. It may be preferable for the load-bearing end ofrebar 131, which may ultimately be inserted into support bore 123, to becut as nearly as possible to 90° relative to vertical portion 135 toprevent loading and punching. Rebar 131 may be secured in bore 131 atthe time of manufacture or later in the field. Further, although aconsiderably more complicated endeavor, rebar 131 may be cast in placein support 99 during manufacture.

A description of the process used to form various embodiments of thesupport of the present invention is best continued with reference tosupport 143, although the process may be used to form any of supports51, 85, 99, or 143 in the previous FIGS. 1 through 10 or any of supports287, 301, and 315 in subsequent FIGS. 15 through 17.

FIG. 14 is a cross-sectional view of a compartment 217 in form 215 ofFIG. 11 which has been outfitted to form a support such as bi-levelsupport 143 of FIGS. 7 and 8, for example. A first bearing pad insert265 may be adjacent floor 219, including a dowel 267 for forming bore173. A step insert 269 may be installed adjacent second short side wall227 and floor 219. A liner 271 may be installed adjacent first shortside wall 221, step insert 269 and side wall 227. A firstcylindrically-shaped shear key insert 275 may be installed adjacentliner 271 along first short side wall 221, and a secondcylindrically-shaped shear key insert 277 may be installed adjacentliner 271 along step insert 269. An angled shear key insert 279 may beinstalled adjacent second short side wall 227. A second bearing padinsert 281 is shown adjacent step insert 269 and second short side wall227, including inverted anchoring arm 177 with nailhead 179. Compartment217 may be filled with concrete 283 by process similar to that describedin FIG. 13.

FIG. 15 is a top view of a support 287. A bearing pad 289 may have abore 191 and an anchoring arm 193, either singly or in combination.Three sloped sides 295 extend between bearing pad 189 and the outsideedge of a base 297. Sides 295 may include shear keys 296, which maynumber greater or fewer than shown. Support 287 may have an overallfrusto-pyramidal shape with “N” sides, where N represents the totalnumber of sides, which may range from three (as in support 287 of FIG.15) to any intermediate number between three and infinity (see FIG. 16,for example, where N is 8) to an infinite number of sides, which mayresult in a frusto-conical shaped support (see FIG. 17, for example).

FIG. 16 is a top view of a support 301 which represents an exemplarintermediate step in the progression of support shapes possible as thenumber of sides N of a given frusto-pyramidal support approachesinfinity. Support 201 may include bearing pad 303 with bore 305,anchoring arm 307, or any combination thereof. Eight sloped sides 309(i.e., N=8) may extend between bearing pad 303 and the outside edge of abase 311, but N may be any number, and, as N approaches infinity, afrusto-conical shaped support such as that in FIG. 17 may result. Sides309 may include shear keys 310, which may number greater or fewer thanshown.

FIG. 17 is a top view of a support 315 which may have a bearing pad 317with bore 319, anchoring arm 321, or any combination thereof. A single,continuous sloped side (N=∞) 323 may extend between bearing pad 317 andthe outside edge of a base 325, which may result in an overallfrusto-conical shaped support 315. Side 323 may include shear key 324,which may be continuous along side 323 as shown or may be discontinuousalong side 323 such as in FIG. 18.

FIG. 18 is a top view of support 329 which may have anelliptically-shaped bearing pad 331, bore 333, pair of anchoring arms335, or any combination thereof. Like support 315 of FIG. 17, support329 may have a single, continuous sloped side (N=∞) 337 extendingbetween bearing pad 331 and the outside edge of an elliptically-shapedbase 339, which may result in an overall elongate frusto-conical shapedsupport 329. Side 337 may include opposing shear keys 341, which mayalternatively be continuous along side 337 such as shear key 324 ofsupport 315 of FIG. 17.

Although the invention has been derived with reference to particularillustrative embodiments thereof, many changes and modifications of theinvention may become apparent to those skilled in the art withoutdeparting from the spirit and scope of the invention. Therefore,included within the patent warranted hereon are all such changes andmodifications as may reasonably and properly be included within thescope of this contribution to the art.

1. A support structure comprising: a body having a bottom surface and atop surface, and wherein the body has at least one inclusion between thetop surface and the bottom surface for vertically anchoring the supportstructure in a finished concrete slab.
 2. The support structure recitedin claim 1 wherein the area of the bottom surface is greater than thearea of the top surface.
 3. The support structure recited in claim 2wherein the shape of the support structure is at least one offrusto-pyramidal and frusto-conical.
 4. The support structure recited inclaim 2 and further comprising an anchoring structure.
 5. The supportstructure recited in claim 4 wherein the anchoring structure a has afirst end, a second end, and a midsection extending between the firstand second ends.
 6. The anchoring structure recited in claim 5 whereinthe midsection includes at least one bend.
 7. The anchoring structurerecited in claim 5 wherein at least one of the first and second ends ofthe anchoring structure has a circumference which is greater than thecircumference of the midsection.
 8. The support structure recited inclaim 4 wherein the anchoring structure is a bore extending into thesupport structure.
 9. The anchoring structure recited in claim 8 andfurther comprising a support member having a first end, a second end,wherein the support structure includes at least one bend and wherein thefirst end of the support member is supported within the bore.
 10. Thesupport structure recited in claim 4 wherein the length of the bottomsurface exceeds the width of the bottom surface.
 11. The supportstructure recited in claim 10 wherein the top surface of the supportstructure comprises at least a first section at a first height relativeto the bottom surface, and a second section at a second height relativeto the bottom surface, and wherein the height of the first sectionexceeds the height of the second section.
 12. A process formanufacturing a support structure comprising the steps of: providing aform having a floor and a side wall, and having a height, length, andwidth which correspond to a set of desired support dimensions; placing afirst bearing pad insert, having at least one of a support groove and athrough bore, onto the floor of the form; performing at least one ofinserting a dowel into a through bore on the bearing pad insert, thesize of the dowel corresponding with the dimensions of the support boreto be formed in the support structure, and inserting an invertedanchoring arm into a support groove on the bearing pad insert; placing afirst shear key insert within the form; pouring a concrete mixture intothe form and allowing the concrete mixture to set; and after allowingthe support structure to cure completely, removing the support structurefrom the form.
 13. The process recited in claim 12, and furthercomprising the step of lining the form with a non-stick liner prior toinstalling the shear key insert.
 14. The process recited in claim 12,and further comprising the step of coating the liner with a releasingagent prior to pouring the concrete mixture.
 15. The process recited inclaim 12, and further comprising the step of applying a sealant betweenthe bearing pad insert and the form prior to pouring the concretemixture.
 16. The process recited in claim 12 and wherein the pouring aconcrete mixture into the form step includes the steps of pouring asuccession of concrete layers and smoothing each layer before thesubsequent layer is poured.
 17. The process recited in claim 12 andfurther comprising the step of selecting a second bearing pad insertwhich includes at least one of a support groove and a through bore andplacing the second bearing pad insert into the form on top of a stepinsert provided adjacent the side wall.
 18. The process recited in claim12, and further comprising the steps of: providing a high-strengthreinforcing member which has been right-angle cut to a specified lengthand has been angled to form a first end and a second end; applying acement to the first end of the reinforcing member; and inserting thefirst end of the reinforcing member into the support bore to fix thereinforcing member into the support structure.
 19. A process for using asupport structure comprising the steps of: determining the sitedesignated for concrete slab placement; placing a support structurehaving a body with a top surface and a bottom surface, the top surfaceincluding at least one of an anchoring arm and an elevated supportmember, atop at least one of grade and decking; and pouring concrete toa level over the support structure to form a concrete slab.
 20. Theprocess recited in claim 19 and further comprising the steps of securingat least one of a component of a reinforcing mat or a component of apost-tension cable to at least one of the anchoring arm and elevatedsupport member.